What are the differences between NoSQL and a traditional RDBMS?The important note here is that eschewing relations (foreign key) support in the database/server infrastructure relieves the database/servers from the load and lock-management overhead of maintaining referential integrity. The consequence of this, the trade-off, is that referential integrity, consistency, and the other ACID concerns are then pushed out to the applications. Many applications benefit from this rather than being limited by it. (Some applications have to be wedged into the client/server model).

Mar29

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Is REINDEX dangerous?I'm thinking I was mistaken about it being row level security. Further reading suggests that it's more about the MVCC "visibility" (are some of those rows still locked in transactions which have yet to be committed).

Is REINDEX dangerous?I read somewhere that COUNT(*) performance issues in PostgreSQL can be caused by the need for the server to check the permissions on every tuple during the table scan (to determine which rows are visible to the entity performing the query).